[microformats-discuss] Extending the embedded information

[Tantek Ç elik]

On 7/1/05 3:03 PM, "Carl Beeth" <carl.beeth at gmail.com> wrote:

> I'm very excited about the microformats, seems I have been looking for
> something like this for ages. I Even found a old mail from 98 in the
> w3c html discussion list where we talk along those lines.
> <http://lists.w3.org/Archives/Public/www-html/1998Apr/0016.html>
> 
> Although I am all for embedding semantics in web pages, I'm missing
> one thing in the microformats: a way to semantically link to more
> complete version of the information when one does not want to pollute
> the page with all the information.
> 
> Here is an example from the site:
> <div class="vcard">
> <a class="url fn" href="http://tantek.com/">
> Tantek Çelik
> </a>
> <div class="org">Technorati</div>
> </div>
> 
> Now what if we wanted to have a to make more information available
> with out necessarily displaying it in the web page. maybe something
> like this:
> 
> <div class="vcard">
> <a class="url fn" href="http://tantek.com/">
> Tantek Çelik
> </a>
> <div class="org">Technorati</div>
> <a href="http://tantek.com/vcard.txt" class="vcardfile">vcard</a>
> </div>
> 
> The reason the class is important in on the link is that it allows the
> user agent/crawler to identify what is behind the link. a possible
> alternative would be to use type="text/vcard" but sadly I think they
> are supposed to be mimetypes but could not find the mime type for
> vcard

One of the key prerequisites for proposing a microformat is to first exhaust
the possibilities of using 1. a semantic XHTML element (or attribute), and
2. a semantic XHTML compound.

In otherwords, if you can do it with semantic XHTML, you don't need (and
shouldn't propose) a microformat.  Re-use before inventing.

In this case you are trying to develop a mechanism for linking to an
"alternate" version of something.

This is precisely what rel="alternate" (defined in HTML4) does.

As far as claiming what is at the other end of a link, that is not something
that you can reliably do from the source of a link.  Heck, the destination
of the link might not even exist.  This is fundamental to the web.  All you
can do is provide a hint.

Now you might say that rel="alternate" is insufficient because it doesn't
distinguish between an "abstract" and a "full" version, or, as others have
found in other contexts (e.g. localization/translation), the "original"
version, and a "copy" or a "translation".

That's a discussion worth having, as I think there is enough of a need there
to propose an elemental microformat to address one or more of those use
cases.  However, I do think that a single rel value might suffice for this,
rather than a class name for each microformat.  The latter seems like an
unnecessary explosion in the number of class names.

For now though, just use rel="alternate" to link to a page that contains
another version of your hCard, perhaps a more complete version.  That should
actually be sufficient for a user agent/crawler to go get the complete
version.

Thanks,

Tantek